Side-effect of lockdown: Delhi's air cleanest in 5 years
On Tuesday morning, Delhi's air quality improved to the "good" category, following favorable wind speed and good rainfall during the last month. The national capital city recorded an Air Quality Index (AQI) of 48 at 9 am today. The curbs imposed to contain the spread of COVID-19 have also been considered responsible for the improvement. Here are more details on this.
On Monday, Delhi recorded a 24-hour average AQI of 41, the lowest since the Central Pollution Control Board (CPCB) started maintaining air quality records five years ago. Notably, AQI between 0 and 50 is considered "safe," 51-100 is labeled "satisfactory," 101-200 "moderate," 201-300 "poor," 301-400 "very poor," while 401-500 falls under "severe," category. AQI above 500 falls under "severe" and "emergency" categories.
It should be noted that Monday was the fifth "good" air quality day for Delhi this year. The capital city had recorded favorable AQI values of 45, 50, 50 and 45 on March 28, August 13, August 20 and August 24, respectively. Furthermore, through August, air quality values remained between 50 and 70 on most days.
A CPCB official said that the improvement in Delhi's air quality could be attributed to favorable weather, including good wind speed and plenty of rainfall, as well as the restrictions imposed for the COVID-19 pandemic. Delhi recorded 236.5 mm rainfall this August, said to be the highest in the past seven years. For next few days, intermittent "light to moderate" rains have been predicted.
Earlier in April, after the first coronavirus-induced lockdown was imposed across the country, the pollution level in Delhi had reduced to a five-year low. In fact, the presence of PM 2.5 pollutant in the city's air dropped by nearly four times during March 25 to April 1, as compared to the corresponding period of time last year.